Apron conveyor



Patented Oct. 7, 1947 CONVEYQR Jervis B. `Webb, Bloomfield Hlls, Mich., assignor to Jervis B. 'Webb Company, Detroit, Mich., a corporation of Michigan Application November 23, 1945, Serial No. 630,274:v

6 Claims.

This invention relates to a pan or apron type of conveyor having a chain driving means for p-roviding movement.

Conveyor systems of the type employed to move sand, gravel, small parts and the like have generally been constructed with bottom members and side aprons simulating insofar as possible a continuous enclosed channel with means provided in the bottom surface for preventing the load from sliding While traveling up or down an inclined plane. Such conveyors are normally provided with articulating sections which permit their travel around a sprocket at the beginning and end of a conveyor line. The use of overlapping members is generallyemployed in order to provide iiexibility and prevent `insofar as possible leakage of material carried in therconveyor. `One of the principal problems in developing a conveyor of this type is to provide a construction at the joints where articulation occurs which will prevent or avoid insofar as possible leakage o f material throughout the main course ofthe conveyor line, as well as around the forward sprocket to the point where the material carried is unloaded.

It is the principal object of the present invention to provide a newl type of construction for the pan or apron members which will effectively prevent leakage of material such as sand, gravel, etc.

Another object of this invention is to provide a conveyor of extremely simple and economical construction.

A further object of the invention is to provide a means of transmitting motion to the conveyor which will utilize a chain drive preferably of the keystone type.

Still another object of the invention is to provide roller means for supporting the chain drive which will in turn support the load carrying members.

A still further object of the invention is to provide a bottom pan construction with overlapping members which will articulate about an axis which coincides with the axis of the supporting member which transmits the load to the chain.

Another object of the invention is to provide a means of locking adjacent pan sections in position so that the material carried will not be able to enter between the overlapping sections and thus raise them out of proper position.

A further objectof the invention is to provide a tubular means of supporting the load carrying pans which will in turn be supported by cylinder extensions formed asa part of the locking pins of a chain such asthe keystonechain.

(C1. IBS-496) Stil1 another object of the invention is to provide overlapping side members which will prevent leakage of material when the conveyor is turning around the forward sprocket, as well as during the straightaway course of the conveyor.

A still further object of the invention is to provide an irregular line for attaching the side members to the bottom members which will add to the rigidity of such side members against bending or distortion.

Another object of the invention is to provide a bottom contour for the load carrying surface which will prevent sliding of the material when the conveyor is traveling on an incline.

These and other objects will appear more clearly from a detailed description ofthe preferred embodiment of the invention and from an examination of the drawings forming a part of this application wherein,A

Figure l is a transverse cross sectional elevation of the apron conveyor.

Figure 2 is a longitudinal cross sectional elevation taken along the line 2-2 of Fig. 1.

Figure 3 is a fragmentary sectional side elevation of a single bottom pan and side member showing the line of attachment between such members.

Figure 4 is a perspective View of the side -bars I4 and center link I5 of the chain drive showing the special locking pin I6 used in the present con struction.

In the drawings Iii represents the rotatably mounted rollers on which the driving chains II are carried. These rollers are provided at thev outer end with flanges I2 which guide the chain drives in the correct path of the conveyor. The rollers Il) are mounted on a shaft I3 which eX- tends through the rollers and is supported at each end by a suitable journal which will permit rotation of the shaft and rollers. Such journals, not shown, are supported in a suitable manner by ythe floor or structural members which form the main support for the conveyor line. The rollers I2 are spaced longitudinally at a distance equivaient to the length of .several links of the, chain drive and the load intermediate such rollers is carried by the chain drive itself.

The cylindrical extension of the locking pin I5 ts into the end of the tube I1 which extends transversely across the conveyor. The bottom section of the load carrying pan I8 is formed at the rear end I9 in a generally cylindrical shape with the inside diameter 2li somewhat larger than the outside diameter of the tube Il as shown in Figures 2 and 3.

is formed with the rear end 22 substantially on a perpendicular line with the'center of the rear end I9 of the pan i8 and with the forward edge 23' well ahead of the center of the arc forming the forward end 29 of the pan I8 and inclined forward toward the top of the apron. Y Y i A section 24 of the rear end of the apron 2i adjacent to the rear end of the pan I9 is cutout'to accommodate the forward end of the next adjacent pan. This cut out section 24 extends far enough so that when the adjacent pans are assembled on a horizontal line, some clearance will exist between the end of the cut out section v25` and the forward end of the adjacent pan 26. This permits the pans to change direction from a horizontal position to a somewh-at upwardly Vinclined position.

The side apron just above the cut out section 24 serves to lock the forward end of the next adjacent Ypan in'its normal overlapping position and prevents particles of the load being carried from entering between the overlapping surfaces causing them to-separate and permit leakage of the material. This locking means is effective Ywhile the sections of the apron conveyor are making a turn around the sprocket as 4well as while'they are intheir normal carrying and return positions. The apron member 2l is joined to the pan member I8 in a continuous weld from the end of the cut out section 25 to the end of the pan member 26. The construction of adjacent-pan and apron members is identical except that the Yapron membersl2| are alternately welded to overlap from the inside and from the outside the apron members of adjacent pans. The outside apron members are welded along the outside edge and theinside apron members along the inside edge in order to provide proper clearance between the overlapping apron members at the edge where they are joined to the pan members. Y .f

As shown in Figure 2, the apron member `2| overlaps from the outside the forward end of adjacent apron members 2l and the rearward end of apron 28` and apron member 2B overlaps from i the inside the forward portion of 2l and rearward portion-of apron member 3l.

The forward lower end 3!! of the apron 27 is shaped to extend around the forward edge 26 of pan I8. This construction is provided-in order to close up the clearance between the forward edge 26 of the pan I8 and the end 25 of the cut out section 24 of the next adjacent apron, thereby preventing any leakage of material through such clearance opening. l

As shown in Figure 2, the topy edges of the apron members form a substantially continuous straight line during normal operation, the height of such line determining the depth of the load that may be carried. Y

We see from the abo-ve description that a large number of desirable objectives have been accomplished by the above construction which is extremely economical of fabrication and assembly and which provides a strong leak-'proof apron conveyor system for fine materials such as Sand,

4 gravel, etc., or for the conveyance of small miscellaneous parts. The tendency of a load to stretch conveyor members apart is entirely absorbed by the strong keystone chain which, in addition, serves as a drive means for the conveyor system. Thus, the only load borne by individual pan members is the vertical load of thermaterial resting on each pan.

While the above description relates to a specific embodiment of this invention, it will be understood that numerous alterations could be made in the detail of the construction without departing from the spirit of the invention, as set out in the following claims. Y I claim: Y Y

'1. An endless apron conveyor characterized by transverse cylindrical load supporting members, means for movably mounting said members, bottom pan members having forward and rearward ends formed as segments of cylindrical arcs, one of said ends partially encircling and being supported by'one of saidtransverse cylindrical members, the other of said ends overlying the rst mentioned end of an adjacent bottom pan Ymemk ber, each ofV said ends articulating about the axes of said transverse cylindrical members, overlapping side apron members joined to said bottom pan members, and the said overlying end of said bottom pan members being held in position by the side apron members of adjacent pans.

2. An endless apron conveyor characterized by transverse Ycylindrical load supporting members, means for movably mounting said members, bottom pan members having forward and rearward ends formed as segments of cylindrical arcs, one loi? said ends partially encircling and being supported by one of said transverse cylindrical members, the other of said ends overlying the first mentioned endof an adjacent bottom pan member, each of said ends articulating about the axes of said transverse cylindrical members, overlapping side apron members continuously joined to said bottom pan members except at one end, where an opening is provided for accommodating the said overlying end of the adjacent bottom pan member, clearance being provided between the edge of said overlying end and the adjacent edge of said apron member to provide for limited articulationin a direction opposite to that required to make a turn at the end of the conveyor line. Y Y

3. An endless apron conveyor characterized by transverse Vcylindrical load supporting members, means for movably mounting said members, bottom pan members having forward and rearward ends formed as segments of cylindrical arcs, one

member; clearance being provided between the edge of said overlying end and the adjacent edge of said apron member, the apron member attached to said overlying edge continuing around and past the edge of said end covering from the side the clearance between said edge and the adj acent apron member. Y

4. An endless conveyor characterized by a double endless chain drive, said chains being movably supported on rotatably mounted rollers, said chains being provided with locking pins having integrally formed cylindrical extensions, transverse tubular load supporting members being mounted at their ends on said cylindrical eX- tensions of said locking pins and being thereby supported, bottom pan members having forward and rearward ends formed as segments of cylindrical arcs, one of said ends partially encircling and being supported by one of said transverse tubular members, the other of said ends overlying the rst mentioned end of an ajdacent bottom pan member, each of said ends articulating about the axes of said transverse tubular members, overlapping side apron members continuously joined to said bottom pan members except at one end where an opening is provided for accommodating the said overlying end of the adjacent bottom pan member, clearance being provided between the edge of said overlying end and the adjacent edge of said apron member, the apron member attached to said overlying edge continuing around and past the edge of said end covering from the side the clearance between said edge and the adjacent apron member.

5. An endless apron conveyor comprising a pair of laterally spaced endless chains, means of movably supporting said chains relative to a building structure, a, plurality of longitudinally spaced cylindrical load supporting members mounted between said chains, a plurality of load carrying members mounted on said load supporting members in a manner permitting articulation thereon, each of said load carrying members comprising a single bottom pan and two side apron members characterized by the rearward portion of each bottom pan member being formed to partially encircle one of said cylindrical load carrying members, the central portion of each bottom pan member being formed to incline upwardly in a forward direction, the forward portion of each bottom pan member being formed to rest upon the rearward portion of the adjacent bottom pan member, and the aprons attached to said adja- 6 cent bottom pan member having their rearward portions formed to overlie said forward portion of each bottom pan member locking it into position.

6. An endless apron conveyor comprising a pair of laterally spaced endless chains, means of movably supporting said chains relative to a building structure, a plurality of longitudinally spaced cylindrical load supporting members mounted between said chains, a plurality of load carrying members mounted on said load supporting members in a manner permitting articulation thereon, each of said load carrying members comprising a single bottom pan and two side apron members characterized by the rearward portion of each bottom pan member being formed to partially encircle one of said cylindrical load carrying members, the central portion of each bottom pan member being formed to incline upwardly in a forward direction, the forward portion of each bottom pan member being formed to rest upon the rearward portion 0f th'e adjacent bottom pan member, the aprons attached to said adjacent bottom pan member having their rearward portions formed to overlie said forward portion of each bottom pan member locking it into position and the forward portions of each of said side apron members overlapping alternately from within and without the rearward portions of adjacent side apron members to an extent which prevents any opening in said side apron members which would permii-I leakage of material from occurring.

JERVIS B. WEBB.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 945,616 Schwartz Jan. 4, 1910 1,731,609 Brayton Oct. 15, 1929 2,037,904 Hogg Apr. 21, 1936 

